Ef Deal’s fantastic Twins of Bellesfées series—Esprit de Corpse, Aeros & Heroes, and The Order of Duval—reimagines the landscape of 19th century France with shapeshifters, vampires, and all manner of retrofuturistic technology. She talks about why she chose that time and place to give life to her brand of horror-infused steampunk, what it was like to grow up in a haunted house, and the “wonderful letter” that made her think she would never be a published novelist; lucky for us, she kept going anyway.